unstick the lid of a metal martini shaker
If it's a metal shaker, try this. Put it in the oven at about, oh, 250 degrees. For oh, 5 minutes or so. Just long enough to heat the metal up. Then take it directly from the oven and stick it in the freezer for another 5 or so minutes. This will cause the metal to expand and contract, and may loosen it up enough to get the top off.
Are you really impatient for that drink?
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